#include <unistd.h>
#include <linux/loop.h>
#include <linux/dm-ioctl.h>
-#include <libudev.h>
#include "list.h"
#include "mount-setup.h"
#include "umount.h"
#include "path-util.h"
#include "util.h"
+#include "virt.h"
+#include "libudev.h"
+#include "udev-util.h"
typedef struct MountPoint {
char *path;
dev_t devnum;
- bool skip_ro;
- LIST_FIELDS (struct MountPoint, mount_point);
+ LIST_FIELDS(struct MountPoint, mount_point);
} MountPoint;
static void mount_point_free(MountPoint **head, MountPoint *m) {
assert(head);
assert(m);
- LIST_REMOVE(MountPoint, mount_point, *head, m);
+ LIST_REMOVE(mount_point, *head, m);
free(m->path);
free(m);
}
static int mount_points_list_get(MountPoint **head) {
- FILE *proc_self_mountinfo;
- char *path, *p;
+ _cleanup_fclose_ FILE *proc_self_mountinfo = NULL;
unsigned int i;
- int r;
assert(head);
- if (!(proc_self_mountinfo = fopen("/proc/self/mountinfo", "re")))
+ proc_self_mountinfo = fopen("/proc/self/mountinfo", "re");
+ if (!proc_self_mountinfo)
return -errno;
for (i = 1;; i++) {
- int k;
+ _cleanup_free_ char *path = NULL;
+ char *p = NULL;
MountPoint *m;
- char *root;
- bool skip_ro;
-
- path = p = NULL;
-
- if ((k = fscanf(proc_self_mountinfo,
- "%*s " /* (1) mount id */
- "%*s " /* (2) parent id */
- "%*s " /* (3) major:minor */
- "%ms " /* (4) root */
- "%ms " /* (5) mount point */
- "%*s" /* (6) mount options */
- "%*[^-]" /* (7) optional fields */
- "- " /* (8) separator */
- "%*s " /* (9) file system type */
- "%*s" /* (10) mount source */
- "%*s" /* (11) mount options 2 */
- "%*[^\n]", /* some rubbish at the end */
- &root,
- &path)) != 2) {
+ int k;
+
+ k = fscanf(proc_self_mountinfo,
+ "%*s " /* (1) mount id */
+ "%*s " /* (2) parent id */
+ "%*s " /* (3) major:minor */
+ "%*s " /* (4) root */
+ "%ms " /* (5) mount point */
+ "%*s" /* (6) mount options */
+ "%*[^-]" /* (7) optional fields */
+ "- " /* (8) separator */
+ "%*s " /* (9) file system type */
+ "%*s" /* (10) mount source */
+ "%*s" /* (11) mount options 2 */
+ "%*[^\n]", /* some rubbish at the end */
+ &path);
+ if (k != 1) {
if (k == EOF)
break;
log_warning("Failed to parse /proc/self/mountinfo:%u.", i);
-
- free(path);
continue;
}
- /* If we encounter a bind mount, don't try to remount
- * the source dir too early */
- skip_ro = !streq(root, "/");
- free(root);
-
p = cunescape(path);
- free(path);
-
- if (!p) {
- r = -ENOMEM;
- goto finish;
- }
+ if (!p)
+ return -ENOMEM;
/* Ignore mount points we can't unmount because they
* are API or because we are keeping them open (like
continue;
}
- if (!(m = new0(MountPoint, 1))) {
+ m = new0(MountPoint, 1);
+ if (!m) {
free(p);
- r = -ENOMEM;
- goto finish;
+ return -ENOMEM;
}
m->path = p;
- m->skip_ro = skip_ro;
- LIST_PREPEND(MountPoint, mount_point, *head, m);
+ LIST_PREPEND(mount_point, *head, m);
}
- r = 0;
-
-finish:
- fclose(proc_self_mountinfo);
-
- return r;
+ return 0;
}
static int swap_list_get(MountPoint **head) {
- FILE *proc_swaps;
+ _cleanup_fclose_ FILE *proc_swaps = NULL;
unsigned int i;
- int r;
assert(head);
continue;
}
- if (endswith(dev, "(deleted)")) {
+ if (endswith(dev, " (deleted)")) {
free(dev);
continue;
}
free(dev);
if (!d) {
- r = -ENOMEM;
- goto finish;
+ return -ENOMEM;
}
if (!(swap = new0(MountPoint, 1))) {
free(d);
- r = -ENOMEM;
- goto finish;
+ return -ENOMEM;
}
swap->path = d;
- LIST_PREPEND(MountPoint, mount_point, *head, swap);
+ LIST_PREPEND(mount_point, *head, swap);
}
- r = 0;
-
-finish:
- fclose(proc_swaps);
-
- return r;
+ return 0;
}
static int loopback_list_get(MountPoint **head) {
- int r;
- struct udev *udev;
- struct udev_enumerate *e = NULL;
+ _cleanup_udev_enumerate_unref_ struct udev_enumerate *e = NULL;
struct udev_list_entry *item = NULL, *first = NULL;
+ _cleanup_udev_unref_ struct udev *udev = NULL;
+ int r;
assert(head);
- if (!(udev = udev_new())) {
- r = -ENOMEM;
- goto finish;
- }
+ udev = udev_new();
+ if (!udev)
+ return -ENOMEM;
- if (!(e = udev_enumerate_new(udev))) {
- r = -ENOMEM;
- goto finish;
- }
+ e = udev_enumerate_new(udev);
+ if (!e)
+ return -ENOMEM;
- if (udev_enumerate_add_match_subsystem(e, "block") < 0 ||
- udev_enumerate_add_match_sysname(e, "loop*") < 0) {
- r = -EIO;
- goto finish;
- }
+ r = udev_enumerate_add_match_subsystem(e, "block");
+ if (r < 0)
+ return r;
- if (udev_enumerate_scan_devices(e) < 0) {
- r = -EIO;
- goto finish;
- }
+ r = udev_enumerate_add_match_sysname(e, "loop*");
+ if (r < 0)
+ return r;
+
+ r = udev_enumerate_add_match_sysattr(e, "loop/backing_file", NULL);
+ if (r < 0)
+ return r;
+
+ r = udev_enumerate_scan_devices(e);
+ if (r < 0)
+ return r;
first = udev_enumerate_get_list_entry(e);
udev_list_entry_foreach(item, first) {
MountPoint *lb;
- struct udev_device *d;
+ _cleanup_udev_device_unref_ struct udev_device *d;
char *loop;
const char *dn;
- if (!(d = udev_device_new_from_syspath(udev, udev_list_entry_get_name(item)))) {
- r = -ENOMEM;
- goto finish;
- }
+ d = udev_device_new_from_syspath(udev, udev_list_entry_get_name(item));
+ if (!d)
+ return -ENOMEM;
- if (!(dn = udev_device_get_devnode(d))) {
- udev_device_unref(d);
+ dn = udev_device_get_devnode(d);
+ if (!dn)
continue;
- }
loop = strdup(dn);
- udev_device_unref(d);
-
- if (!loop) {
- r = -ENOMEM;
- goto finish;
- }
+ if (!loop)
+ return -ENOMEM;
- if (!(lb = new0(MountPoint, 1))) {
+ lb = new0(MountPoint, 1);
+ if (!lb) {
free(loop);
- r = -ENOMEM;
- goto finish;
+ return -ENOMEM;
}
lb->path = loop;
- LIST_PREPEND(MountPoint, mount_point, *head, lb);
+ LIST_PREPEND(mount_point, *head, lb);
}
- r = 0;
-
-finish:
- if (e)
- udev_enumerate_unref(e);
-
- if (udev)
- udev_unref(udev);
-
- return r;
+ return 0;
}
static int dm_list_get(MountPoint **head) {
- int r;
- struct udev *udev;
- struct udev_enumerate *e = NULL;
+ _cleanup_udev_enumerate_unref_ struct udev_enumerate *e = NULL;
struct udev_list_entry *item = NULL, *first = NULL;
+ _cleanup_udev_unref_ struct udev *udev = NULL;
+ int r;
assert(head);
- if (!(udev = udev_new())) {
- r = -ENOMEM;
- goto finish;
- }
+ udev = udev_new();
+ if (!udev)
+ return -ENOMEM;
- if (!(e = udev_enumerate_new(udev))) {
- r = -ENOMEM;
- goto finish;
- }
+ e = udev_enumerate_new(udev);
+ if (!e)
+ return -ENOMEM;
- if (udev_enumerate_add_match_subsystem(e, "block") < 0 ||
- udev_enumerate_add_match_sysname(e, "dm-*") < 0) {
- r = -EIO;
- goto finish;
- }
+ r = udev_enumerate_add_match_subsystem(e, "block");
+ if (r < 0)
+ return r;
- if (udev_enumerate_scan_devices(e) < 0) {
- r = -EIO;
- goto finish;
- }
+ r = udev_enumerate_add_match_sysname(e, "dm-*");
+ if (r < 0)
+ return r;
- first = udev_enumerate_get_list_entry(e);
+ r = udev_enumerate_scan_devices(e);
+ if (r < 0)
+ return r;
+ first = udev_enumerate_get_list_entry(e);
udev_list_entry_foreach(item, first) {
MountPoint *m;
- struct udev_device *d;
+ _cleanup_udev_device_unref_ struct udev_device *d;
dev_t devnum;
char *node;
const char *dn;
- if (!(d = udev_device_new_from_syspath(udev, udev_list_entry_get_name(item)))) {
- r = -ENOMEM;
- goto finish;
- }
+ d = udev_device_new_from_syspath(udev, udev_list_entry_get_name(item));
+ if (!d)
+ return -ENOMEM;
devnum = udev_device_get_devnum(d);
dn = udev_device_get_devnode(d);
-
- if (major(devnum) == 0 || !dn) {
- udev_device_unref(d);
+ if (major(devnum) == 0 || !dn)
continue;
- }
node = strdup(dn);
- udev_device_unref(d);
-
- if (!node) {
- r = -ENOMEM;
- goto finish;
- }
+ if (!node)
+ return -ENOMEM;
- if (!(m = new(MountPoint, 1))) {
+ m = new(MountPoint, 1);
+ if (!m) {
free(node);
- r = -ENOMEM;
- goto finish;
+ return -ENOMEM;
}
m->path = node;
m->devnum = devnum;
- LIST_PREPEND(MountPoint, mount_point, *head, m);
+ LIST_PREPEND(mount_point, *head, m);
}
- r = 0;
-
-finish:
- if (e)
- udev_enumerate_unref(e);
-
- if (udev)
- udev_unref(udev);
-
- return r;
+ return 0;
}
static int delete_loopback(const char *device) {
- int fd, r;
+ _cleanup_close_ int fd = -1;
+ int r;
- if ((fd = open(device, O_RDONLY|O_CLOEXEC)) < 0)
+ fd = open(device, O_RDONLY|O_CLOEXEC);
+ if (fd < 0)
return errno == ENOENT ? 0 : -errno;
r = ioctl(fd, LOOP_CLR_FD, 0);
- close_nointr_nofail(fd);
-
if (r >= 0)
return 1;
}
static int delete_dm(dev_t devnum) {
- int fd, r;
- struct dm_ioctl dm;
+ _cleanup_close_ int fd = -1;
+ int r;
+ struct dm_ioctl dm = {
+ .version = {DM_VERSION_MAJOR,
+ DM_VERSION_MINOR,
+ DM_VERSION_PATCHLEVEL},
+ .data_size = sizeof(dm),
+ .dev = devnum,
+ };
assert(major(devnum) != 0);
- if ((fd = open("/dev/mapper/control", O_RDWR|O_CLOEXEC)) < 0)
+ fd = open("/dev/mapper/control", O_RDWR|O_CLOEXEC);
+ if (fd < 0)
return -errno;
- zero(dm);
- dm.version[0] = DM_VERSION_MAJOR;
- dm.version[1] = DM_VERSION_MINOR;
- dm.version[2] = DM_VERSION_PATCHLEVEL;
-
- dm.data_size = sizeof(dm);
- dm.dev = devnum;
-
r = ioctl(fd, DM_DEV_REMOVE, &dm);
- close_nointr_nofail(fd);
-
return r >= 0 ? 0 : -errno;
}
assert(head);
LIST_FOREACH_SAFE(mount_point, m, n, *head) {
+
+ /* If we are in a container, don't attempt to
+ read-only mount anything as that brings no real
+ benefits, but might confuse the host, as we remount
+ the superblock here, not the bind mound. */
+ if (detect_container(NULL) <= 0) {
+ /* We always try to remount directories
+ * read-only first, before we go on and umount
+ * them.
+ *
+ * Mount points can be stacked. If a mount
+ * point is stacked below / or /usr, we
+ * cannot umount or remount it directly,
+ * since there is no way to refer to the
+ * underlying mount. There's nothing we can do
+ * about it for the general case, but we can
+ * do something about it if it is aliased
+ * somehwere else via a bind mount. If we
+ * explicitly remount the super block of that
+ * alias read-only we hence should be
+ * relatively safe regarding keeping the fs we
+ * can otherwise not see dirty. */
+ mount(NULL, m->path, NULL, MS_REMOUNT|MS_RDONLY, NULL);
+ }
+
+ /* Skip / and /usr since we cannot unmount that
+ * anyway, since we are running from it. They have
+ * already been remounted ro. */
if (path_equal(m->path, "/")
#ifndef HAVE_SPLIT_USR
|| path_equal(m->path, "/usr")
#endif
- ) {
- n_failed++;
+ )
continue;
- }
- /* Trying to umount. Forcing to umount if busy (only for NFS mounts) */
- if (umount2(m->path, MNT_FORCE) == 0) {
- log_info("Unmounted %s.", m->path);
+ /* Trying to umount. We don't force here since we rely
+ * on busy NFS and FUSE file systems to return EBUSY
+ * until we closed everything on top of them. */
+ log_info("Unmounting %s.", m->path);
+ if (umount2(m->path, 0) == 0) {
if (changed)
*changed = true;
return n_failed;
}
-static int mount_points_list_remount_read_only(MountPoint **head, bool *changed) {
- MountPoint *m, *n;
- int n_failed = 0;
-
- assert(head);
-
- LIST_FOREACH_SAFE(mount_point, m, n, *head) {
-
- if (m->skip_ro) {
- n_failed++;
- continue;
- }
-
- /* Trying to remount read-only */
- if (mount(NULL, m->path, NULL, MS_MGC_VAL|MS_REMOUNT|MS_RDONLY, NULL) == 0) {
- if (changed)
- *changed = true;
-
- mount_point_free(head, m);
- } else {
- log_warning("Could not remount as read-only %s: %m", m->path);
- n_failed++;
- }
- }
-
- return n_failed;
-}
-
static int swap_points_list_off(MountPoint **head, bool *changed) {
MountPoint *m, *n;
int n_failed = 0;
assert(head);
LIST_FOREACH_SAFE(mount_point, m, n, *head) {
+ log_info("Deactivating swap %s.", m->path);
if (swapoff(m->path) == 0) {
if (changed)
*changed = true;
continue;
}
- if ((r = delete_loopback(m->path)) >= 0) {
-
+ log_info("Detaching loopback %s.", m->path);
+ r = delete_loopback(m->path);
+ if (r >= 0) {
if (r > 0 && changed)
*changed = true;
mount_point_free(head, m);
} else {
- log_warning("Could not delete loopback %s: %m", m->path);
+ log_warning("Could not detach loopback %s: %m", m->path);
n_failed++;
}
}
continue;
}
- if ((r = delete_dm(m->devnum)) >= 0) {
-
- if (r > 0 && changed)
+ log_info("Detaching DM %u:%u.", major(m->devnum), minor(m->devnum));
+ r = delete_dm(m->devnum);
+ if (r >= 0) {
+ if (changed)
*changed = true;
mount_point_free(head, m);
} else {
- log_warning("Could not delete dm %s: %m", m->path);
+ log_warning("Could not detach DM %s: %m", m->path);
n_failed++;
}
}
int umount_all(bool *changed) {
int r;
bool umount_changed;
-
LIST_HEAD(MountPoint, mp_list_head);
- LIST_HEAD_INIT(MountPoint, mp_list_head);
-
+ LIST_HEAD_INIT(mp_list_head);
r = mount_points_list_get(&mp_list_head);
if (r < 0)
goto end;
if (r <= 0)
goto end;
- r = mount_points_list_remount_read_only(&mp_list_head, changed);
-
end:
mount_points_list_free(&mp_list_head);
int r;
LIST_HEAD(MountPoint, swap_list_head);
- LIST_HEAD_INIT(MountPoint, swap_list_head);
+ LIST_HEAD_INIT(swap_list_head);
r = swap_list_get(&swap_list_head);
if (r < 0)
int r;
LIST_HEAD(MountPoint, loopback_list_head);
- LIST_HEAD_INIT(MountPoint, loopback_list_head);
+ LIST_HEAD_INIT(loopback_list_head);
r = loopback_list_get(&loopback_list_head);
if (r < 0)
int r;
LIST_HEAD(MountPoint, dm_list_head);
- LIST_HEAD_INIT(MountPoint, dm_list_head);
+ LIST_HEAD_INIT(dm_list_head);
r = dm_list_get(&dm_list_head);
if (r < 0)
~ianmdlvl / elogind.git / blobdiff